This invention relates to a device for continuously cleaning yarn and more specifically, for removing lubricants and contaminants during the processing of fibers used to make surgical sutures.
The removal of processing lubricants and associated contaminants is a significant aspect in the processing of surgical ligatures such as braided sutures, woven tapes and yarns. The difficulty in cleaning the surgical ligatures stems from the fact that the contaminants and lubricants can be trapped between the individual filaments of the yarn bundle in these surgical ligatures. In order to clean the ligature, a cleaning agent or solvent must permeate the crevices between the filaments of the yarn bundle. Typically, surgical ligatures have been cleaned by various batch methods, where the ligature is immersed in a bath for a predetermined amount of time sufficient to remove lubricants and contaminants from the fibers.
The present invention provides a solution to the above-mentioned problem by providing a device that continuously cleans yarn fibers, and which does not require any stoppage or interruption in the yarn manufacturing process in order to clean such ligatures.
Venturi devices, such as that disclosed in U.S. Pat. Nos. 3,097,412; 3,462,813; 3,545,057; 3,577,614; 3,863,309; 3,881,231; 3,969,799; 3,979,805; 4,041,583; 4,096,612; 4,104,770; 4,157,605; 4,189,812 and 4,290,177; all incorporated herein by reference, have been used for texturizing yarns, but not for cleaning lubricants and contaminants from yarns.
It is therefore an object of the present invention to provide a device for continuously cleaning a ligature.
Another object of the present invention is to provide a device for removing lubricants and contaminants during the processing of surgical ligatures.
Still another object of the present invention is to provide a method for continuously cleaning surgical ligatures moving through a device.
A further object of the invention is to provide a method for removing lubricants and contaminants during the processing of surgical ligatures.
These and other objects and advantages of the invention will become more fully apparent from the description and claims, which follow or may be learned by the practice of the invention.
The present invention is directed to a method and apparatus for continuously cleaning a surgical ligature moving through the device. A first scouring body has a yarn entrance and a yarn exit connected by a central cavity. Moving fluid is introduced through the surgical ligature while the surgical ligature is positioned within and moving through the central cavity.
In a particularly preferred embodiment, a device in accordance with the present invention further comprises an inlet in fluid communication with the central cavity of the scouring body, and a venturi situated within the central cavity. The venturi is preferably positioned at the exit. The venturi devices listed in the background, and incorporated by reference, would all be used in the present invention. In one preferred embodiment, a needle is slidably mounted into the central cavity through the entrance of the venturi. The needle includes a passage there through for introducing ligature through the central cavity and, at least one flange and a cap. The flange of the needle has at least one opening to allow movement of the fluid from the solvent inlet to the central cavity. This preferred device further comprises at least one cover for holding the needle securely within the central cavity of the scouring body and at least one adjustment nut for adjusting movement of the needle within the central cavity. The cover is in direct contact with the adjustment nut. The device also preferably includes ceramic eyelets situated adjacent to the entrance of the scouring body. In an alternative preferred embodiment, the cleaning device has a baffle for guiding the ligature. The baffle is slidably mounted on a bracket affixed to the scouring body at the exit. A turning pin may also be provided for holding the baffle in the bracket. The entrance and exit are preferably located on opposing sides of the scouring body.
A ligature cleaning system in accordance with the present invention preferably includes two of the scouring bodies described above. Like the first scouring body, the second scouring body has a entrance and exit connected by a central cavity and a means for introducing fluid through the ligature while the ligature is positioned within and moving through the central cavity of the second scouring body. The first and second scouring bodies are arranged in tandem. Each of the first and second scouring bodies has an axis defined by its entrance and exit. The axis of the first and second scouring bodies can be co-axially aligned along a common axis when the system is in its thread-up state. The axes of the first and second scouring bodies are then aligned at a non-zero angle in order to bring the system into a scouring state. The angle between the axes of the first and second scouring bodies is from about 45xc2x0 to about 90xc2x0. When the system is used to clean thinner ligature, the non-zero angle varies from about 60xc2x0 to about 75xc2x0. Separation of the liquid stream containing contaminants and lubricants from the ligature fiber occurs when the ligature fiber is guided away from the exit of a scouring body at an angle. A plurality of scouring bodies can be aligned to continuously clean surgical ligatures.
The ligature cleaning system can also include a housing for encasing a scouring body and a rotatable mounting device for attaching the scouring body within the housing. The housing comprises eyelets for introducing and removing ligature. The housing can also include a fume hood for removing vapors emitted by the cleaning fluid.
The device of the present invention can also comprise a fluid reservoir and a connecting means for transporting solvent from the reservoir to a scouring body. The preferred cleaning fluid is ethyl acetate and the ligature fiber is a suture strand.
The present invention also relates to a method of continuously cleaning a ligature moving through a device. The method comprises the following steps: (a) guiding ligature through a scouring body having a entrance and exit connected by a central cavity, and (b) introducing fluid through ligature positioned within and moving through the central cavity. Before employing step (a), a needle can be slidably mounted into the central cavity and the ligature can be introduced into the central cavity using a needle. After the needle is mounted, the movement of the needle can be adjusted with an adjustment nut. Before employing step (b), the ligature can be moved through a second scouring body having entrance and exit connected by a central cavity, and then the first and second scouring bodies can be aligned at a non-zero angle. The angle between the first and second bodies can vary from about 45xc2x0 to about 90xc2x0.
The method of the present invention can also include the following steps of: (a) axially aligning at least two scouring bodies during a thread-up state; (b) guiding ligature through the central cavity of the scouring bodies utilizing an axially slidable needle; (c) rotatably adjusting the scouring bodies creating a non-zero angle; and (d) introducing fluid through the central cavities of the scouring bodies while moving the ligature through the central cavities of the scouring bodies, thereby cleaning the ligature of contaminants and undesired lubricants during a scouring state.